Few DimWatt readers will disagree that the UK must remain dependent on fossil fuel until such time as we can persuade investors to overcome the barriers to new nuclear which “environmentalists”, politicians and even the general public are erecting against this relatively safe and secure energy source.

However, even the most optimistic enthusiast for new nuclear power cannot hope to see this on line before 2020 at the earliest. If the UK can replace its existing nuclear capacity before 2030, then the UK will be doing exceptionally well.

So, until then, we will be using fossil fuel for 85% of our electricity generation, virtually all our transport energy and most of our heating needs.

Unfortunately, as Euan Mearn’s chart so vividly illustrates, we are almost out of our own fossil fuel resources. May be we can revive our coal mining. Some DimWatt readers tell me we have masses of coal left. Some of which we can mine and others that must be burned or gasified in-situ. But for oil and gas, we must depend either on imports - or a miracle. So there can be little doubt that if the optimists are right and shale gas (and oil) can “come to the rescue”, in time, it will be a wonderful thing.

In fact, in DimWatt’s submission to the Electricity Market Review we urge the Government to investigate, as a matter of urgency, whether the UK has promising resources of untapped shale oil and gas and whether these can be extracted economically and in an environmentally acceptable manner in time to allow the UK’s transition to what will inevitably a “post carbon” future in time to avert a potentially crippling import dependency.

During the past few years, shale gas has become a very significant source of energy in the USA.

The remarkable entry of shale gas into the American energy mix is very recent. It seems to have arrived just in time to replace conventional resources which were in sharp decline during the last decade

It is written by David Hughes, an eminently qualified and mature, Canadian geoscientist.

Unfortunately (for my taste) the author shares the view of many "peak oilists" who hold to the curious view that anthropogenic emissions of greenhouse gases can increase when it seems to be increasingly clear (from price signals) that the global extraction of all fossil fuels is most unlikely to grow as fast as demand. "Geological fundamentals" as well as politics will, frighteningly, threaten the cheap energy on which our prosperity and civilisation depends. High energy prices and actual scarcity will cause the next (and imminent) major Global recession. God help the more than one billion and growing very poor.

To be fair, the subject which Mr Hughes writes about is energy consumption and extraction in the USA. So much of his report, while technically interesting, will be of only academic interest to UK-based observers. While the USA is indeed a significant oil importer, it will be self-sufficient in coal for many years to come. Unlike the UK, there are still domestic possibilities for opening up new oil frontiers both offshore east and west, as well as in the US Arctic.

But the section (pages 17 - 35) which deal with gas is particularly interesting. The conventional wisdom has lately become that shale gas is so plentiful and so cheap to produce, using new drilling and extraction technology, that it can “save America’s bacon”. Gas (and oil) from these resources can deliver new power. It can replace oil as a transport fuel. It can be used in the gas networks to replace dwindling supplies of conventional gas. Shale gas, can by the sheer quantity of it locked up in the rocks, ease America and may be the rest of the world, towards a more (hateful word) "sustainable" future if only its extraction could realise the promise of its promoters.

Unfortunately for us all, it seems that it cannot without substantial price rises that, among many other things, require its extraction to be environmentally acceptable. The more one looks into this, the less acceptable large-scale shale gas extraction looks. The report is replete with photos that show the environmental impact of existing operations in the Marcellus. These environmental effects have caused some European countries, notably France, to halt even the exploratory drilling for shale gas. Possibly these photos are cherry picked to make the point, and it would be good to hear from US readers of DimWatt whether these photos and experiences are generic or unusual.

Apart from extensive land use, the environmental issues are water use, waste water treatment, water table contamination, leaking methane, high depletion rates, etc. Astonishingly, David Hughes does not examine the energy investment that is needed to deliver the extracted energy from shale gas operations. This is something we urge the Post Carbon Institute to ask him to review.

It is the section on shale gas that caught DimWatt’s eye. We hope that our readers can add to this debate as, without a new fossil reserve like this, our country may cease to be viable in the very short term. Lofty ambitions for 2050 can smash into a million tiny splinters if we cannot get past 2015 without a severe energy crisis.